Introduction
The engine control system on the diavel uses a sensor that measures the temperature of the coolant (engine temperature). This sensor has a resistance of ntc type (negative temperature coefficient), that reduces its own value when the temperature increases. The engine temperature sensor, allows the control unit to manage correctly the cold starting and the heating phases.
Components assembling position

The engine temperature sensor is mounted on the left hand side of the vertical cylinder.
Location of engine temperature sensor connector.
Wiring diagram

Ccm engine control connection, s engine temperature sensor. 1 Green/white - g/w, 2 black/purple - bk/v.
In the event of fault
In the event of an engine temperature sensor fault, the engine control unit implements a recovery value of 70C and activates the radiator fans.
Fault codes generated and possible correlated faults
Fault codes generated by the engine control unit and displayed by the dds (engine temperature sensor diagnosis):
Note
Check integrity of electric circuit - short-circuit to vdc = with dashboard on, using a voltmeter, a voltage is measured between the wire tested and ground.
Check integrity of electric circuit - short-circuit to ground = with the battery cables disconnected, using an ohmmeter, continuity is detected between the wire tested and ground.
Check integrity of electric circuit - open circuit = with the battery cables disconnected, using an ohmmeter, no continuity is detected between the two ends of the wire tested.
The tank dashboard shows the error "engine temperature" and the eobd warning light activates.
When the dashboard receives the "engine temperature" error, flashing dashes are displayed instead of the temperature reading. If the dashboard does not receive engine temperature information from the can line, the error "engine temperature" is not shown on the display, but flashing dashes are still displayed instead of the temperature reading.

Possible correlated faults: inadequate engine power, irregular idle speed (target idle speed is 1350 rpm with engine stabilised at operating temperature), the engine does not start easily, radiator fans not activated correctly or not activated at all, causing the coolant to reach boiling point.
Check:
The engine temperature value may be checked using the dds. Check that the value given is plausible.
If none of the aforementioned tests identify the problem and the engine temperature sensor is in proper working order, replace the engine control unit.
component replacement methods
No special measures are necessary in order to replace the engine temperature sensor. After replacement of the engine temperature sensor, reset the self-adaptive parameters relative to carburation with the dds.
Air temperature sensor
Absolute pressure sensorsDraining the clutch hydraulic circuit
Warning
Clutch fluid will damage painted surfaces if spilled on them. It is
also very harmful if it comes into contact with the skin or
with the eyes; in the case of accidental contact, wash the affected area
thoroughly with plenty of running water.
Remove the dust cap to expose the bleed val ...
Removal of the intake manifold and coolant union
Loosen the clips (f) and remove the hoses (t).
Remove the manifolds (25) undoing the screws (21).
Loosen the clamp (a) and remove the hose (b). Remove the union (12) and
recover the seal (24).
...
Refitting the oil pump
If removed, apply specific threadlocker on the bushing (7) outer thread, and
screw it in the crankcase half, observing the
height.
Position the reference bushings (15) and the oil sealing o-rings (2) and (4)
according to the crankcase lubrication
channels.
Position the oil pump on th ...